Scratch Little Brute Original Design / Scratch Built

Scratch - Little Brute {Scratch}

Contributed by Matt Gillard

Manufacturer: Scratch

scratch_bigbrute_with_littlebruteBrief:
This is me first attempt o' a scale change. T' Big Brute is a rocket that I built a few years back but have never flown. Aye aye! Begad! With t' 2008 challenge callin' for a scale change on a rocket, I thought I’d might as well get somethin' from t' original Big Brute. Aye aye! Lookin' through me collection o' nose cones, t' only one with t' same profile as t' Big Brute was a 13mm diameter nose cone, me hearties, shiver me timbers, me bucko, t' rest o' t' scalin' followed givin' a minimum diameter tumble recovery small brute.

Construction:
Parts need

  • 2.2" BT-5 body tube
  • Launch lug
  • 1/16" balsa sheet
  • Nose cone from a defunct Estes fireflash - (P/N 072600, PNC-5A)
  • Clay mass
Also used was
  • Bostik glue
  • Pink spray paint
  • Pink paper
  • Black tape
  • A photocopier
T' scale from t' nose cone was t' be a 7.5 downscale which is about 13-14% o' t' original. Ya scallywag! Aye aye! This makes t' body tube t' be 2.2 inches long. Avast, me proud beauty! Blimey! T' fins were down scaled from t' original usin' a photocopier t' make a template. Aye aye! See EMRR featured tips on how t' do this.

scratch_littlebrute_onthepadApart from that t' rocket builds itself. Blimey! My major concern that unlike all t' min diameter 13mm rockets that I have flown in t' past, this rocket does nay has much in t' way o' aft fins that lower t' CP t' somewhere safe. Avast, me proud beauty! T' 13mm motor really does lower t' CG, so I added 3g o' clay t' t' nose cone. Blimey! Ya scallywag! I used Spacecad t' check things out and it came back okay.

T' whole rocket be painted pink t' match me original Big Brute, me bucko, felt tip marker was used t' black out t' fins. Blimey! Three strips o' black tape were added t' give t' strips. Arrr! T' name o' t' rocket, Little Brute be printed on pink paper and then glued into place. Blimey! Ya scallywag! I could nay brin' myself t' put t' original name in such a small rocket.

scratch_littlebrute_failedrecoveryFlight:
First flight was on a 1/2A3-4T motor. Ahoy! Take off be very fast. Begad! At about 100 feet it took a right angle turn and shot off sideways. Avast! Blimey! On recovery, arrr, t' little brute be nose cone buried and had stripped its launch lug. Aye aye! Spacecad predicted 472 feet, arrr, this flight be nowhere near that.

After gluin' a new longer lug, me hearties, two more flights were made a few days later on 1/4A3-3T motors. Avast! Each time t' flight be arrow straight with no deviation from t' flight path seen. Blimey! On each recovery t' little brute buried itself in t' soft earth. Ya scallywag! Ya scallywag! spacecad version 3 does nay have t' 1/4AT motor profile. I imagine that version 4 does.

Summary:
Pro: It's small and I can get motors for it, ya bilge rat, unlike t' big brute where I have t' get an explosive license and have t' police visit me house every year t' see a wooden box.

Con: Ballistic recovery - never good.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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